1. Field of the Invention
This invention relates to a shifting mechanism for a manual change-speed transmission, in particular for use in motor cars.
2. Description of the Prior Art
A shifting device of this type, known from the European Pat. Specification No. 00 35 223, has two axially spaced shift-finger locking-wheel systems disposed on a single gear-selector shaft. Accumulative tolerances on the gear-selector shaft, on the one hand, and on the housing parts connected to one another, on the other hand, may lead to difficulties and failure in shifting.
Such difficulties could, of course, be overcome by generously dimensioning the tolerances of the cooperating parts, but this would lead to the preselection and shifting movements of the gear-selector being insufficiently performed and indefinite.
The object of the invention is, therefore, to provide an improved shifting mechanism such that, despite the accumulative tolerances which occur, trouble-free shifting among all the gear ratios is possible.
This object is attained according to the invention in a shifting mechanism having a first selector finger carried by a gear-selector shaft for engaging one or the other of two shift forks and a second selector finger carried by the gear-selector shaft for engaging a third shift fork. The selector fingers cooperate with respective locking wheels that are secured axially to separate, connected gear box housings to prevent axial movement of the shift forks other than the fork selected for movement. At least one of the locking wheels is fixed to its associated gear box housing by way of an axially adjustable attachment.
Because the axial fixing of the second locking wheel may be adjusted axially, the accumulative tolerances occurring on the gear-selector shaft and accumulative tolerances different from these tolerances on the housing parts are compensated in a simple manner that permits trouble-free shifting of all the gears.